Spinal cord injuries (SCIs) are sustained by an increasing number of patients each year worldwide. The treatment of SCIs has long been a hard nut to crack for doctors around the world. Mesenchymal stem cells (MSCs) have shown benefits for the repair of SCI and recovery of function. Our present study aims to investigate the effects of intravenously infused human umbilical cord blood-derived MSCs (hUCB-MSCs) on functional recovery after subacute spinal cord compression injury of two noncontinuous segments. In addition, we compared the effects of single infusion and repeated intravenous (i.v.) injections on the recovery of spinal cord function. A total of 43 adult rabbits were randomly divided into four groups: control, single injection (SI), repeated injection at a 3-day (3RI) or repeated injection at a 7-day interval (7RI) groups. Non-immunosuppressed rabbits in the transplantation groups were infused with either a single complete dose or three divided doses of 2 × 106 hUCB-MSCs (3-day or 7-day intervals) on the first day post decompression. Behavioural scores and somatosensory evoked potentials (SEPs) were used to evaluate hindlimb functional recovery. The survival and differentiation of the transplanted human cells and the activation of the host glial and inflammatory reaction in the injured spinal cord were studied by immunohistochemical staining. Our results showed that hUCB-MSCs survived, proliferated, and primarily differentiated into oligodendrocytes in the injured area. Treatment with hUCB-MSCs reduced the extent of astrocytic activation, increased axonal preservation, potentially promoted axonal regeneration, decreased the number of Iba-1+ and TUNEL+ cells, increased the amplitude and decreased the onset latency of SEPs and significantly promoted functional improvement. However, these effects were more pronounced in the 3RI group compared with the SI and 7RI groups. Our results suggest that treatment with i.v. injected hUCB-MSCs after subacute spinal cord compression injury of two noncontinuous segments can promote functional recovery through the differentiation of hUCB-MSCs into specific cell types and the enhancement of anti-inflammatory, anti-astrogliosis, anti-apoptotic and axonal preservation effects. Furthermore, the recovery was more pronounced in the rabbits repeatedly injected with cells at 3-day intervals. The results of this study may provide a novel and useful treatment strategy for the transplantation treatment of SCI.

Background: Percutaneous kyphoplasty (PKP) can effectively treat osteoporotic vertebral compression fractures (OVCFs). Although satisfactory clinical outcomes can be achieved, bone cement leakage remains a primary complication of PKP. Previous studies have found many high risk factors for bone cement leakage into the spinal canal; however, less attention to the posterior wall morphologies of different vertebral bodies may be one reason for the leakage. Here, we investigated the effect of posterior vertebral wall morphology in OVCF patients on bone cement leakage into the spinal canal during PKP. Methods: Ninety-eight OVCF patients with plain computed tomography (CT) scans and three-dimensional (3D) reconstruction images from T6 to L5 were enrolled. 3D-CT and multiplanar reconstructions (MPR) were used to measure the concave posterior vertebral wall depth (PVWCD) and the corresponding midsagittal diameter of the nonfractured vertebral body (VBSD), and the PVWCD/VBSD ratio was calculated. All subjects were divided into the thoracic or lumbar groups based on the location of the measured vertebrae to observe the value and differences in the PVWCD between both groups. The differences in PVWCD and PVWCD/VBSD between the thoracic and lumbar groups were compared. Three hundred fifty-seven patients (548 vertebrae) who underwent PKP within the same period were also divided into the thoracic and lumbar groups. The maximal sagittal diameter (BCSD), the area of the bone cement intrusion into the spinal canal (BCA), and the spinal canal encroachment rate (BCA/SCA × 100%) were measured to investigate the effect of the thoracic and lumbar posterior vertebral wall morphologies on bone cement leakage into the spinal canal through the Batson vein during PKP. Results: The PVWCDs gradually deepened from T6 to T12 (mean, 4.6 mm); however, the values gradually became shallower from L1 to L5 (mean, 0.6 mm). The PVWCD/VBSD ratio was approximately 16% from T6 to T12 and significantly less at 3% from L1 to L5 (P < 0.05). The rate of bone cement leakage into the spinal canal through the Batson vein was 10.1% in the thoracic group and 3.7% in the lumbar group during PKP. In the thoracic group, the BCSD was 3.1 ± 0.5 mm, the BCA was 30.2 ± 3.8 mm², and the BCA/SCA ratio was 17.2 ± 2.0%. In the lumbar group, the BCSD was 1.4 ± 0.3 mm, the BCA was 14.8 ± 2.2 mm², and the BCA/SCA ratio was 7.4 ± 1.0%. The BCSD, BCA and BCA/SCA ratio were significantly higher in the thoracic group than in the lumbar group (P < 0.05). Conclusions: The PVWCD in the middle and lower thoracic vertebrae can help reduce bone cement leakage into the spinal canal by enabling avoiding bone cement distribution over the posterior 1/6 of the vertebral body during PKP. The effect of the difference between the thoracic and lumbar posterior vertebral wall morphology on bone cement leakage into the spinal canal through the Batson vein in OVCF patients during PKP is one reason that the rate of bone cement leakage into the thoracic spinal canal is significantly higher than that into the lumbar spinal canal.

Background: Severe traumatic cervical spinal cord injury (tcSCI) is a disastrous event for patients and families. Maximizing spinal cord function recovery has become the primary therapeutic goal. This study investigated the effect of early extensive posterior decompression on spinal cord function improvement after severe tcSCI.Methods: A retrospective review of 83 consecutive patients who underwent extensive open-door laminoplasty decompression within 24 h after severe tcSCI (American Spinal Injury Association (ASIA) impairment scale (AIS) grade A to C) between 2009 and 2017 at our institution was performed. The patient clinical and demographic data were collected. Neurological functional recovery was evaluated according to the Japanese Orthopaedic Association (JOA) score system, ASIA motor score (AMS) and AIS grade.Results: Among the 83 patients initially included, the baseline AIS grade was A in 12, B in 28, and C in 43. Twenty-three patients (27.7%) had a high cervical injury. Cervical spinal stenosis (CSS) was identified in 37 patients (44.6%). The mean intramedullary lesion length was 59.6 ± 20.4 mm preoperatively and 34.2 ± 13.3 mm postoperatively (p < 0.0001). At the final follow-up visit, an improvement of at least one and two AIS grades was found in 75 (90.4%) and 41 (49.4%) patients, respectively. 24 (64.9%) patients with an improvement of least two AIS grades had CSS. The mean AMS and JOA score were significantly improved at discharge and the final follow-up visit compared with on admission (p < 0.0001).Conclusions: Our results suggest that early expansive laminoplasty decompression may improve neurological outcomes after severe tcSCI, especially in patients with CSS. Larger and prospective controlled studies are needed to validate these findings.

Objective: The purpose of this study was to evaluate the feasibility of a novel technique named spinal joints release (SJR) and observe its efficacy in treating rigid post-traumatic thoracolumbar kyphosis (RPTK). Methods: RPTK patients who were treated by SJR with facet resection, limited laminotomy, clearance of the intervertebral space, and release of the anterior longitudinal ligament through the intervertebral foramen and disc of injury segment from August 2015 to August 2021 were reviewed. Intervertebral space release, internal fixation segment, operation time, and intraoperative blood loss were recorded. The intraoperative, postoperative, and final follow-up complications were observed. An improvement in the VAS score and ODI index was observed. Spinal cord functional recovery was evaluated by American Spinal Injury Association Impairment Scale (AIS). Improvement of local kyphosis (Cobb angle) was evaluated by radiography. Results: Forty-three patients were successfully treated by the SJR surgical technique. Open-wedge anterior intervertebral disc space was performed in 31 cases, and repeated release and dissection of the anterior longitudinal ligament and callus were performed in 12 cases. There was no lateral annulus fibrosis release in 11 cases, the anterior half release of lateral annulus fibrosis in 27 cases, and complete release in five cases. There were five cases of screw placement failure in one or two side pedicles of the injured vertebrae due to excessive resection of the facets and improper pre-bending of the rod. Sagittal displacement occurred in four cases at the released segment due to the complete release of bilateral lateral annulus fibrosus. Autologous granular bone + Cage was implanted in 32 cases, and autologous granular bone was implanted in 11 cases. There were no serious complications. The average operation time was 224 ± 31 min, and intraoperative blood loss was 450 ± 225 mL. All the patients were followed up with an average of 26 ± 8.5 months. The VAS scores and ODI index improved significantly at the final follow-up. All of the 17 patients with incomplete spinal cord injury achieved more than one grade of neurological recovery at the final follow-up. An 87% correction rate of kyphosis was achieved and maintained, with the Cobb angle decreasing from 27.7° preoperatively to 5.4° at the final follow-up. Conclusion: Posterior SJR surgery for patients with RPTK has the advantages of less trauma and less blood loss, and kyphosis correction is satisfactory.